NEW YORK — Media mogul Rupert Murdoch said yesterday that he was leaning toward dropping the online subscription fee for The Wall Street Journal in a gamble to increase visitor traffic and Web site advertising revenue.

Murdoch made the comments at a media investment conference, a few months before his News Corp. is scheduled to complete its $5 billion purchase of Dow Jones & Co., the owner of the Journal, http://wsj.com, Barron's and the Dow Jones News Service.

A decision on dropping the subscription fee, which generates an estimated $30 million annually, has not been made but is "right on the front burner" of issues News Corp. is considering as it finalizes the takeover of Dow Jones, Murdoch said at the conference sponsored by Goldman Sachs.

http://wsj.com is by far the most successful media site to charge a subscription fee. About a million readers pay either $99 annually for an online-only subscription or $49 if they also subscribe to the paper.

News Corp. is betting that dropping the http://wsj.com subscription fee will be more than offset by an increase in ad revenue. Making the online Journal free could boost the site's worldwide audience to more than 30 million, and advertisers probably would pay more for the increased traffic and the chance to reach the site's affluent and well-educated audience, Murdoch said.